A "Chronometre Royal" ... or not ...

Caliber is certainly a P1008BS, I can't see the number bur surely 50920X, that is alright for a CR.

Case number 351155 ... well ok... but if the cylindrical part doesn't shock me, the lugs are quite surprisingm reminding some later references...

Now hands and dial are not what is normally associated with "Chronometre Royal" , I would suppose this is a franken coming with different parts especially for ahnds and dial... but that case? is there any reference with that sort of case?

I would not be surprised if the case and movement match. I wasn't sure about the dial at first...but now I think it may be correct. I've only seen chronometers (and not just CRs) with markers that go down to 1/5 of a second.

The hands bother me, as I only expect Alpha hands on a CR from that time period.

hmm hands are also for me problematic, the Alpha are very typical of CR in that period (with the special counterweight shape), I do not have another example in mind.

And if the hands are not original, then there is a strong doubt on the dial, and the dial is also typical of the CR, there are some rare exceptions of black dial and guilloche but this is excessively rare. And here not a guilloche or a black dial, juste another dial different for the typical CR dial.

Hands imho not correct, dial very doubtful or later addition and all this combined with that surprising case...

I don't say it's all bad but I prefer to stay suspicious for the moment :)